Roberts and Sharp discovered that the genes in adenovirus were split into various segments that were combined during RNA processing. The results started to become widely known in 1975-76 and the key papers were published in 1977. Later this gene organization was found to be common in chromosomal eukaryotic genes. Unlike many Nobel Prize discoveries, this one really was revolutionary. Here's the presentation speech by Professor Bertil Daneholt of the Nobel Assembly of the Karolinska Institute.

Your Majesties, Your Royal Highnesses, Ladies and Gentlemen,

Why do children resemble their parents? This question has probably always fascinated humans, but not until the advent of natural science have we arrived at an increasingly satisfactory answer.

In the middle of the last century, the Austrian monk Gregor Mendel conducted his famous breeding experiments with the garden pea. He concluded that every trait of an individual plant is determined by a set of two genes, one obtained from each parental plant. To Mendel a gene was an abstract concept, which he used to interpret his breeding experiments. He had no idea of the physical properties of genes.

Only in the mid-1940s could it be established that in terms of chemistry, genetic material is composed of the nucleic acid DNA. About ten years later the double helical structure of DNA was revealed. Ever since then, progress within the field of molecular biology has been very rapid, and several Nobel prizes have been awarded in this area of research.

Initially, genetic material was studied mainly in simple organisms, particularly in bacteria and bacterial viruses. It was shown that a gene occurs in the form of a single continuous segment of the long, thread-like DNA, and it was generally assumed that the genes in all organisms looked this way. Therefore, it was a scientific sensation when this year's Nobel Laureates, Richard Roberts and Phillip Sharp, in 1977, independently of each other, observed that a gene in higher organisms could be present in the genetic material as several distinct and separate segments. Such a gene resembles a mosaic. Both Roberts and Sharp analyzed an upper respiratory virus, which is particularly suitable for studies of the genetic material in complex organisms. It soon became apparent that most genes in higher organisms, including ourselves, exhibited this mosaic structure.

Roberts' and Sharp's discovery opened up a new perspective on evolution, that is, on how simple organisms develop into more complex ones. Earlier it was believed that genes evolve mainly through the accumulation of small discrete changes in the genetic material. But their mosaic gene structure also permits higher organisms to restructure genes in another, more efficient way. This is because during the course of evolution, gene segments - the individual pieces of the mosaic - are regrouped in the genetic material, which creates new mosaic patterns and hence new genes. This reshuffling process presumably explains the rapid evolution of higher organisms.

Roberts and Sharp also predicted that a specific genetic mechanism is required to enable split genes to direct the synthesis of proteins and thereby to determine the properties of the cell. Researchers had known for many years that a gene contains detailed instructions on how to build a protein. This instruction is first copied from DNA to another type of nucleic acid, known as messenger RNA. Subsequently, the RNA instruction is read, and the protein is synthesized. What Roberts and Sharp were now stating was that the messenger RNA in higher organisms has to be edited. The required process, called splicing, resembles the work that a film editor performs: the unedited film is scrutinized, the superfluous parts are cut out and the remaining ones are joined to form the completed film. Messenger RNA treated in this manner contains only those parts that match the gene segments. It later turned out that the same parts of the original messenger RNA are not always saved during the editing- there are choices. This implies that splicing can regulate the function of the genetic material in a previously unknown way.

Roberts' and Sharp's discovery also helps us understand how diseases arise. One example is a form of anemia called thalassemia, which is due to inherited defects in the genetic material. Several of these defects cause errors in the editing process during splicing; thus, an abnormal messenger RNA is formed and subsequently also a protein that functions poorly or not at all.

The discovery of split genes was revolutionary, triggering an explosion of new scientific contributions. Today this discovery is of fundamental importance for research in biology as well as in medicine.

Dr. Richard Roberts and Dr. Phillip Sharp,

Your discovery of split genes led to the prediction of a new genetic process, that of RNA splicing. The discovery also changed our view of how genes in higher organisms develop during evolution. On behalf of the Nobel Assembly of the Karolinska Institute I wish to convey to you our warmest congratulations, and I now ask you to step forward to receive the Nobel Prize from the hands of His Majesty the King.

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Principles of Biochemistry 5th edition

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Some readers of this blog may be under the impression that my personal opinions represent the official position of Canada, the Province of Ontario, the City of Toronto, the University of Toronto, the Faculty of Medicine, or the Department of Biochemistry. All of these institutions, plus every single one of my colleagues, students, friends, and relatives, want you to know that I do not speak for them. You should also know that they don't speak for me.

Superstition

Quotations

The old argument of design in nature, as given by Paley, which formerlyseemed to me to be so conclusive, fails, now that the law of natural selection has been discovered. We can no longer argue that, for instance, the beautiful hinge of a bivalve shell must have been made by an intelligent being, like the hinge of a door by man. There seems to be no more design in the variability of organic beings and in the action of natural selection, than in the course which the wind blows.

Charles Darwin (c1880)Although I am fully convinced of the truth of the views given in this volume, I by no means expect to convince experienced naturalists whose minds are stocked with a multitude of facts all viewed, during a long course of years, from a point of view directly opposite to mine. It is so easy to hide our ignorance under such expressions as "plan of creation," "unity of design," etc., and to think that we give an explanation when we only restate a fact. Any one whose disposition leads him to attach more weight to unexplained difficulties than to the explanation of a certain number of facts will certainly reject the theory.

Charles Darwin (1859)Science reveals where religion conceals. Where religion purports to explain, it actually resorts to tautology. To assert that "God did it" is no more than an admission of ignorance dressed deceitfully as an explanation...

Quotations

I have championed contingency, and will continue to do so, because its large realm and legitimate claims have been so poorly attended by evolutionary scientists who cannot discern the beat of this different drummer while their brains and ears remain tuned to only the sounds of general theory.

The essence of Darwinism lies in its claim that natural selection creates the fit. Variation is ubiquitous and random in direction. It supplies raw material only. Natural selection directs the course of evolutionary change.

Rudyard Kipling asked how the leopard got its spots, the rhino its wrinkled skin. He called his answers "just-so stories." When evolutionists try to explain form and behavior, they also tell just-so stories—and the agent is natural selection. Virtuosity in invention replaces testability as the criterion for acceptance.

The first commandment for all versions of NOMA might be summarized by stating: "Thou shalt not mix the magisteria by claiming that God directly ordains important events in the history of nature by special interference knowable only through revelation and not accessible to science." In common parlance, we refer to such special interference as "miracle"—operationally defined as a unique and temporary suspension of natural law to reorder the facts of nature by divine fiat.

Quotations

My own view is that conclusions about the evolution of human behavior should be based on research at least as rigorous as that used in studying nonhuman animals. And if you read the animal behavior journals, you'll see that this requirement sets the bar pretty high, so that many assertions about evolutionary psychology sink without a trace.

Jerry Coyne
Why Evolution Is TrueI once made the remark that two things disappeared in 1990: one was communism, the other was biochemistry and that only one of them should be allowed to come back.

Sydney Brenner
TIBS Dec. 2000
It is naïve to think that if a species' environment changes the species must adapt or else become extinct.... Just as a changed environment need not set in motion selection for new adaptations, new adaptations may evolve in an unchanging environment if new mutations arise that are superior to any pre-existing variations

Douglas Futuyma
One of the most frightening things in the Western world, and in this country in particular, is the number of people who believe in things that are scientifically false. If someone tells me that the earth is less than 10,000 years old, in my opinion he should see a psychiatrist.

Francis Crick
There will be no difficulty in computers being adapted to biology. There will be luddites. But they will be buried.

Sydney Brenner
An atheist before Darwin could have said, following Hume: 'I have no explanation for complex biological design. All I know is that God isn't a good explanation, so we must wait and hope that somebody comes up with a better one.' I can't help feeling that such a position, though logically sound, would have left one feeling pretty unsatisfied, and that although atheism might have been logically tenable before Darwin, Darwin made it possible to be an intellectually fulfilled atheist

Richard Dawkins
Another curious aspect of the theory of evolution is that everybody thinks he understand it. I mean philosophers, social scientists, and so on. While in fact very few people understand it, actually as it stands, even as it stood when Darwin expressed it, and even less as we now may be able to understand it in biology.

Jacques Monod
The false view of evolution as a process of global optimizing has been applied literally by engineers who, taken in by a mistaken metaphor, have attempted to find globally optimal solutions to design problems by writing programs that model evolution by natural selection.